The present invention relates to a vehicular suspension system and a method of controlling a vehicular suspension system.
A vehicular suspension system is known which comprises a plurality of shock absorbers, each including a hydraulic damper. The hydraulic damper includes a valve element having a plurality of positions and an actuator in the form of a pulse or stepper motor drivingly coupled with the valve element. A control unit is operatively coupled with each of the pulse motors. Each of the pulse motors is subject to the control unit such that if a target position is subject to a change, the pulse motor turns concurrently with the occurence of this change to approach or reach the new target position. Since turning of the pulse motor and the subsequent turning of the valve element is resisted by flow of hydraulic fluid passing through the hydraulic damper, occurrence of vibration is unavoidable. However, situations where resonance is induced by the vibration. If the resonance inducing vibration takes place, it is difficult to find the appropriate timing to drive the pulse motor. Thus, the loss of synchronism of the pulse motor is unavoidable in the known system.
Accordingly, an object of the present invention is to improve a vehicular suspension system such that the actuator for the valve element of the adjustable hydraulic damper moves smoothly by avoiding the occurrence of loss of synchronism of the actuator.